Replace egrep with grep -E

[OmeletWithoutEgg]

Pull request template

With the release of grep 3.8 the egrep is obsolete
https://git.savannah.gnu.org/cgit/grep.git/commit/src/egrep.sh?id=a9515624709865d480e3142fd959bccd1c9372d1

Type of changes

• CI
• Bugfix
• Feature
• Generic maintenance tasks
• Documentation content changes
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no URL changes)
• Improving the performance of the project (not introducing new features)
• Other (please describe):

Issue Number: N/A

What is the current behavior?

When using the newest version of egrep the deprecated warning jumps out

egrep: warning: egrep is obsolescent; using grep -E

What is the new behavior?

No egrep warnings

Does this introduce a breaking change?

• Yes
• No

Other information

N/A

[ss-o]

Thank you for your contribution! I will update annexes and other related repositories.

[github-actions]

Pull Request closed and locked due to lack of activity.
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